Oscillation-responsive device.



L. DE FOREST. OSGILLATION RESPONSIVE DEVICE.

APPLICATION FILED MAY 19.1906.

WIT ESSE 5:

I \/E T c1 1 a 4: R i; A7 v/dwnwaz;

- PATENTED NOV. 13, 1906;

UNITED STATES PATENT OFFICE;

LE-E'DE FOREST, OF NEW YORK, N. Y.

OSClLLATlON-RESPONSIVE DEVICE.

- Nassau-7o.

Patented Nov. 13, 1906.

Original application and January 1B, 1906. Serial n. 296,616. Dividedand as application filed May 19,1906.

Serial in. 311,721.

i at all whom nmy-cbncern:

M invention relates to devices for detectsimplicity and 'sensitivenessand one ing eeble electrical'currents or oscillations, in general, andecially such currents or oscillations which are developed inwirelesstelegraph-receiving system's.

The object of my invent on is to provide onder of reat- 3 anoscillationdetector or r which, inasmuch as it does-not depend for itsoperation u on any variation of resistance of an impe ect electricalcontact or any variation of the a parent resistance or counterelectromotive orce of a polarization'cell, requiresno adjustment whenemployed for receiving wireless-telegra signals.

h: With these ob'ects in view, my invention comprises 'a receptacleinclosing a sensitive,-

gaseous conducting medium; a. wave-interce'pting means associated withsaid gaseous conducting medium whereby the feeble elec- 'trical currentsor oscillations resulting from the 'energ absorbed from electromagneticsignal-waves may be impressed upon,said

gaseous conducting medium to alter its conuctivity; and a l-indicatingdevice operatively connect with said gaseous conducting medium wherebyalterations in the conductivity of the latter may be made 111 anifest. I

My invention may best be understood by having reference .to, the drawingwhich accompanies and form'sa part of this specifiw tion and whichillustrates diagrammatically one embodiment of'm invention.

In the drawing,- wirelem-telegrap e figure represents a system pro videdwith one form of the oscillation onsive' device which constitutes thesub ect-.

matter of the present invention.

In t figure, tenna connected with the I are incl A represents a.receiving-an- The elepto earth at E and associated rece tacle B. .Twoelectrodes 6 and, osefiwithin said receptacle, whichmay be partiallyexhausted, and, as shown,

' trode C may be an ordinary incandescentlamp carbon filament, whichisconnected witha battery or other source of electrical energy D. Theelectrode I may be any suitable conductor and is herein shown as a diskof platinum or other. material. The gaseous medium inclo'sed between theelectrodes 0 and I is rendered sensitive to electrical oscil lations bythe radiation of heat from the electrode C, said electrode bein heatedby 'the' source of ener D. The local circuit l containing the battery Hor other source of electrical energy and thetelephone F or othersignal-indicating device is electrically conshown is connected in seriestherewith. The i antenna A may be associated with either electrode andinsuch case the other electrode ma be connect-ed to earth. It will be unerstood, however, that the particular mode of as ociating theoscillation respon sive device with the antenna forms no part of myinvention and that any suitable sys tem of circuits may oscillationresponsive device.

The electro es C and I by the battery H depends upon the nature of thegas intervening be- .tween'said electrodes and upon the degree ofexhaustion maintained within the receptacle B. I have found that fromtwenty-five to one hundred and ten volts is sufficient and by em lo aa-much smal er yo ltage may be used. The conductivity of the gas, whichmay be air, or a gas containing compounds of the halogens or halogen'salts or which may be mercury vapor, is increased suflicientlfy to rendersaid as sensitive to the passa e 0 electrical oscilations across the gay the radiation of heat from the electr e C. The passage of electricaloscillations acrosssaid gap alters the conductivity of the gas in saidgap, prob ably by changing the speed of the ions in said gas, andthereby current variations are prouced in the circuit containing thebattery H, the electrodes C and I, and t e telephone F, causing saidtelephone. to respond. en the telephonqis in series with the battery Hand the electrodes C and oscillations across the gap between said electrodes causes an increase of current through a the telephone and if thetelephone is connectotential to be'impre'ssed upon the I, the passage ofbe employed with said hi her degree of exhaustion cation, Serial No.296,615, filed January 18,

. ed in shunt with said electrodes, the passage I claim 1.oscillation-responsive device comprising a partially-exhaustedreceptacle, two separated electrodes sealed in said'receptacle, meansfor heating-one only of said electrodes, means whereby electricaloscillations may be impressed upon the gaseous medium between saidelectrodes, and a intervening a source of electrical local circuitincluding ener and a signal-indicatin .device electrica connectedwith-said e ectrodesa .2. oscillation-responsive device coinprising apartially-exhausted receptacle, two

.prising a separated e ectrodes sealed in said receptaseparatedelectrodes sealed in said recepta cle, means for heating one only ofsaid elec trodes, means whereby electrical oscillations may be impressedupon the gaseous medium intervening between said electrodes, and a localcircuit including a source of electrical energy and a signal-indicatingdevice connected in series with said electrodes.

3. An oscillation-responsive device comprising a partially-exhaustedrece tacle, two separated electrodes sealed in sand receptacle, a sourceof electric current so associated with one only of said electrodes as torender the gaseous medium intervening between said electrodes sensitiveto electrical oscillations, and a local circuit includin a source ofelectrical energy and a signal-indicating device electrically connectedwith said electrodes.

4. An oscillation-responsive device comartiallyexhausted receptacle;

ole, means for heating one only of said elec 111 between saidelectrodes, and a local circuit including a source of electrical energy'trodes, and a local circuit including a source of electrical energy anda signal mdicating device electrically connected with said electrodes. Y

5. An oscillation-responsive device comprising a receptacle, twoseparated electrodes inclosed within said receptacle, means 5 5 forheating one only of said electrodes, means whereby electricaloscillations may be impressed upon the gaseous medium intervenmg betweensaid electrodes, and a local cir curt includin a source of electricalener anda si a-indicating device electrica y connects with saidelectrodes. 6. An'oscillationeresponsive device comprising a receptacle,two separated elec trodes inclosed within said receptacle, means forheating one only of said electrodes, means whereby electricaloscillations may be impressed upon the gaseous medium interven- 7C and asignaLmdicating device connected in series with said electrodes.

7. An oscillation-responsive device com. prising a rece tacle, twoseparated electrodes inclos within said receptacle, a

' source of electric current so associated with a one only of saidelectrodes as to render the gaseous medium intervening between saidelectrodes sensitive to electrical oscillations, and a local circuitincluding a source of elec- 8o trical energy and asignal-indicating-device electrically connected with said electrodes.

.8. An oscillation-responsive device comprising a receptacle, twoseparated electrodes inclosed within said receptacle, means forheatingone only of said electrodes, and a local circuit including a source ofelectrical ener and a signal-indicatin device electrica y connected withsaid e ectrodes.

' In testimony whereof I have hereunto sub- 0 scribed my name this -l0thday of May, 1906.

DE -FOREST.

Witnesses: V

PHILIP Fmswonrs, GEO. L. LEWIS.

